Two DHCP-clients get same ip address.

I am configuring new RB750Gr3 boards. They are used as home firewall/routers only - no wireless. This is an upgrade from the RB750 for speed.
Each is installed in a different unit in a building served by WebPass. I initially configured the units in the same unit, then moved one to the second unit to complete the installation. While restoring the vpn between the units I pinged one from the other and found neither could see the the other, but they could both see the router:

IP Setup:
Network X.Y.Z.0/24
Unit A: X.Y.Z.5
Unit B: X.Y.Z.123 (initially configured in unit A)
Router X.Y.Z.1

Then I noticed that router B had been given A's IP address in DHCP-client:

Flags: X - disabled, I - invalid

INTERFACE USE-PEER-DNS ADD-DEFAULT-ROUTE STATUS ADDRESS

0 ether1 yes yes bound X.Y.Z.5/24

However, in the ip address, both IPs are listed:

Flags: X - disabled, I - invalid, D - dynamic

ADDRESS NETWORK INTERFACE

0 ;;; defconf
192.168.20.1/24 192.168.20.0 ether2-master
1 X.Y.Z.123/24 X.Y.Z.0 ether1
2 D X.Y.Z.5/24 X.Y.Z.0 ether1

Despite this, everything seems to work internally and if I erase the incorrect Dynamic address in B everything continues to work, but I cannot get the DHCP-client to fetch the correct B address.
Also:
Computers in each network (A,B) can self-check their public ip address and these show correctly: A is A and B is B, however, A cannot ping B, and B cannot ping A, and the dhcp-client is mangled.

I cannot set up a VPN until this is resolved somehow. Suggestions?

Under Interfaces, are any of the MACs identical?

Did you restore a backup of one router on the other? DON’T DO THAT!
If you did that, reset that router to factory defaults and configure it manually.
The only thing you can do is a /export on one router and cut-and-paste parts of the config into the other,
making sure you don’t copy things like mac-address.

The stupid; it burns.

Both routers have identical mac addresses.
Thanks for your help!

Solved